Signaling apparatus and circuits



J. F. TUOMEY. SIGNALING APPARATUS AND Cmcux'rs. ORIGINAL. FILED APR- 24.I919.

Dec. 26, 1922; 1,439,772

BY J1? Zia/4g A TTORNEY INVENTOR.

I Patented Dec. 26 1922..

sr res TELEGRAPH COMPANY, A COBPQBATIONGF NEEV" SIGNALING nrrnniarnsnnnornonrrs,

Original application filedApril 24 1919, Serial No. 292,333. Dividedvand this application filed October 21, 191 9. se i l no. 332,178,.

To (ZZZ whom it may concern:

Be it known that I, donn- F. TooMnY, re-

siding at New fi i'orlr, in the county of New York and State'oi NewYork, have invented certain improvements in Signaling Apparatus andCircuits, or which the following is a specification. v l This inventionrelates to signaling apparatus and circuits and concerns particu- 1olarly apparatus and circuits for signaling over telephone lines. Thepresentapplication is a division of my co-pending application, SerialNo. 292,333" filed April 2%, 1919, for Signaling apparatus and.circuits. 7

The present invention provides rqiparatus which, when a transmissionline is in use from one otiice to an office intermediate its terminals,applies a tone current to the non-used portion oi? the line to indicatethat the said other part thereof is busy. This tone current may becodified to identity the intermediate station using the line. The aboveand various other features and objects of this invention will be readilyunderstood from the following description when considered in connectionwith the accompanying drawing showing a diagrai'nmatic view ot one formand arrangement of apparatus embodying this invention. I

in this drawing reference characters A and C designate the terminaloffices of a long distance line L. The apparatus at oilice C is similarto that at oflice A, and has been i omitted from the drawing in ordertoprevent unnecessary crowding. Intermediate to oflices A and C is anoffice B, the apparatus of which will be described hereinafter.

At station A are answering lamps i and 5,

the former being one of the inward answering lamps for calling an inwardoperator,

andthe latter being one'of the outward an- .swering lamps for signalingto an outward operator. Apparatus is provided at oiiice ii whereby lamps4: and 5 are caused torespend to signaling current coming in on line L,which apparatus comprises a transformer 30, the primary of which isconnected across the line, and the secondary of which is associated withthe grid circuit of a vacuum tube amplifier 31, in accordance with theinvention shown and described in the co-pending application of S. P.Shackleton. Serial No. 226,065, filed April 1, 1918, now Patent No.

ing apparatus.

1,411,385, granted riipril 4, 1922, for signal- The amplified signalingcurrent flows throughrelays 22*a-nd 23 connected in parallel in theoutput circuit of tube 31. These relays are of the'frequ'ency responsivetype, relay 2 2 being responsive onlyto C0 cycle currentand relay 23 to135 cycle'current, so that only one of these relays operates at a time,according to the frequency of the signaling'current.

Wh em'therei ore, 6O cycle current is Lap plied to the line by anoperator at another oiiice, in'a manner described hereinafter, thiscurrent flows through transformerSO and amplifier 31 to relay 22 whichopens its con tact and thus disconnects ground from the winding of aslow-release relay 19, normally energized by current from a battery Relay 19 is thus (lo-energized and operates its 'JOHN F. rooarnr, or Newroan, N. nssrenon 'ronr/rnnronn 'rnrnrnonn'nnn contact to closethecircuit of a lamp relay] 18, which circuit extends from abattery32through the back contact of a cut-off relay 17,].an1p relay 18, backcontact33 of relay 21. and the contact otrelay 19 to ground. Relay 18 isthus energized and closes its front contact 35 which connects battery 32with the inward answeringlump 4380 that this lamp gives the signal tothe inward operator. W I

Relay 19is re-energized as soon asthe 6O cycle signaling current ceasesto come in over the line, andin order to prevent the signal fromdisappearing at lamps until answered by the. operator, relay 18 isprovided with a holding circuit extending from battery 32through its'owncontact 3-: to ground. This circuit holds relay 18 energized and thuscauses'lamp 4: to remain lit even after relay 19 has returned to'itsnormal condition. 2 V

'VVhen the operator responds tolamp Q by inserting the plug 36 of hercord into one of I the jacks, 2, the cord battery 3'7. sends aredisconnected from battery 32 by the cut off relay 17. However, the relay21 is now connected with battery 32'by relay 1?. Re-' lay 21 thereforeholds its front contacts closed and thus connects at front contact 33the circuit of a relay 6 with the back contact of relay 19.Consequently, when relay 19 connects ground to its back contact inresponse to a renewed 60 cycle ringing current, relay 6 is energized andconnects a source of 16 cycle ringing current to the tip and ring of theanswering jack, so thatthis current fiowsthrough the toll cord circuitand causes the toll cord supervisory signal 79 to respend. The inwardoperator is thus notified that the distant operator is again signalingto her.

The circuits and apparatus for the control of lamp 5 are similar tothose of lamp 4t, and need not be separately described. It is sufficientto point out that the relay 28 responsive to the 135 cyclecurrentvcontrols a slow release relay 20, which in turn controls a lamprelay 16 for governing lamp 5. The apparatus of this invention thusselectively responds to'60 and 135 cycle current, so that one or theother position at a terminal office may be called according to thefrequency of current sent over the line.

The manner in which the calling operatormay apply currents of differentfrequencies to the line will nowbe described.

To operate the inwardand outward signal ing lamps of ollice C, there isprovided at station A a source of 60 and a source of'135 cyclecurrent. Arelay 10 normally connects the 60 cycle source to the front contacts l0and 41 of relay 11 and when operated by current fronrbattery 7O itconnects the 135 cycle source to these contacts. Front contacts 40 and41 are normally open but are connected with the line L when relay 11 isenergized.

To signal to the inward operators position at ofiice C, the operatorinserts the plug of her toll cord into jack 2 and operates her ringingkey in the usual manner, so that 16 cycle ringing current is appliedtothe tipand ring of the j acl; and flows over the line conductorsthrough transformer 30 and marginal relay 7. This relay beingselectively responsive to 16 cycle current, operates its contact andthus closes the circuit of relay 11, which circuit extends from battery71, through thewinding of relay 11, through the contact of relay 7 andcontact 57 of a relay 13 to ground. Relay 11 closes contacts a0 and -11and thus applies 60 cycle ringing c .1- rent to line L, which currentflows over the line to the ollice C and there causes response of theinward answering lamp.

To signal to the outward operators position at oflice C, the operator atA .i11serts plug 36 into jack 3. and manipulates her ringing lrey. Assoon as the plug is inserted into the jack, battery 37 causes theoperation of the sleeve relay 15 connected in series with the cut-oil,relay 17, and the sleeve relay causes the energization of the relay 10so that this relay applies 135 cycle current to front cont-acts 4.0 andd1. Nhen, therefore, the operatormanipulates the ringing key and thuscauses the operation of relay 11,

current of a frequency of 135 cycles is sent out over the line to cau ethe response of the outward answering lamp at the ofiice C.

@ffice A is further equipped with a jack 1 for signaling to theoperators position at the intermediate oflice B, this position beingequipped with a signal device responsive only to 16cycle current, aswill be described hereinafter. l Vhen the operator at eilice A insertsthe plug of her cord into jack 1, the sleeve'battery of the cordenergizes the sleeve relay 15$,connected in series with the cutoll relay17, and thus opens at contact 57 of relay 13 the ground connectionforrelay 11. hen the operator then manipula her ringing key 55 andimpresses 16 cycle current on the line conductors, relay 11 fails torespond to relay 7, so that the 16 cycle ringin current flows throughtheback contacts pf relay 11, over theline L to the intermediate station,where it causes response of the signaling apparatuses described be low.It should here be noted that the 16 cycle current thus sent out fromoffice A also reaches oliice C where it flows through the winding ofamarginal relay corresponding to the relay 7 at office A. This rela isso adjusted, however, that. it fails to respond to the current fromo'llice A, and this current consequently has no effect ato'lfice C. An

operator at orlice A is thus enabled to call any one of the otheroperator s positions associated with the line by merely plugging intothe'jack corresponding-to the position she desires to call, andoperating the ringing key. i

The signaling apparatus above referred to for calling an operator at theintermediate sponsiye device may be used, however, when" desired. A ack45 is provided, whereb the operatorunay listen in on the line at anytime to determine whether it is busy, or answer the call S1 1121142 andinquire which oflice, A or C, is calling, so that she may complete theconnection by plugging in on a jack L6 or 4;? according to the directionfrom which the callvoriginates. v

Jacks :6 and i7 provided "witl'i normally closed tip and ring contactswhich interrupt line L only when an operators cord is I insertedtherein. This cord is equipped with a. master ringing key having acontact 61, which in its normal position connects a source ofcycle-current to the contact 63 of the key 64 and in its operatedposition connects a source of 135 cycles-to this contact.-'When,-t-herefore, the operator inserts plug 62 into .jack 46, say, andoperates the key 64 she sends to station A 60 or 135 cycle ringingcurrent according to the position of contact 61. The intermediate oificeoperator may thus call the inward or the outward operator at station 'Aor C, respectively, by using jack 46 or 47.

Connected across the line conductors at the intermediate station B is atransformer intermediate station inserts plug =62 intoone of the jacks,say 46, the relay 48 is energized by current from the sleeve battery 66of the cord. The relay closes its contacts and current from battery 67flows through a the interrupter. This current is applied to the lineconductors by the secondary 49 and flows through the contacts ofjack 47over line L to ofiice C, thereby indicating that the line beyond theintermediate station is in use.

In case there is more than one intermediate oflice on the line it isdesirable to pass the current in the secondary of transformer 49 througha codifying device 75 which interrupts the tone current. at regularintervals and thus breaks it up into telegraphic dots and dashes for thepurpose of notifying the operators which of the intermediate ofiices isbusy. In its present form the device 75 .is a revolving commutator thesegments of which differ for each intermediate ofiice. Any other devicemay be used for rendering the tone current characteristic of the ofiiceat which it is applied tothe line.

Although in the above-described form of embodiment of the invention,there are only three oflices associated with the line it is to beunderstood that a greater number of offices may be associated therewith,asdesired. The number of positions at each oflice selectively calledfrom the other offices may likewise be changed to suit convenience,

it being readily understood that for each additional position it ismerely necessary to provide an additional source, differing in frequencyfrom the other sources, with selective apparatus for applying currentfrom this source to the line and selective signal apparatus forresponding to current of this frequency, similarly as described herein.The frequencies of signallng current used herein are merely illustrativeand any other suitable frequencies may be used when de sired. The inwardand outward positions of the terminal oflices need not be adjacent toeach other, but may be located in separate buildings when conditions ofthe service make this desirable;

, Although only one form of apparatus and circuits embodying thisinvention is shown and described herein, it is to be understood thatvarious changes and modifications may be made therein within the scopeof the following claims without departing from th spirit and scope ofthisinvention.

hat is claimed is: i I .1; In combination, a telephone line, source oftone current at an intermediate point thereof, means at said point for,interru'pting said line and associating an operator with the part ofthe line either. way,

said line than that with which the operator is associated. I a

2. In combination, a telephone line, a source of tone current at anintermediate point thereof, means at said point for interrupting saidline and associating an operator with the line either way from saidpoint, automatic means for associating said source with the otherportion of said line than the one with which the operator is associated,and means for codifying the current from saidsource.

3. Incombination, a telephone line, a cord circuit, jacks intermediatesaid line for associating said circuit with one portion, of said line oranother, a source .oftone current associated with said line, and relaycontrolled by the jacks with which said cord circuit is associated forgoverning said source. i

4. In combination, a telephone line comprising a plurality of sections,contacts normally associating said sections, an opera contacts andconnecting said cord circuit on one side and a device actuated by saidmeans for applying signaling current to a section on the other side.

5. In combination, a telephone line comprising a plurality of sections,a jackasso ciated with each section, contacts and con nectionsassociated with said acks for nor mally maintaining said line inconductive continuity, a cord for co-operating with said jacks, andmeans operative when said cord is associated with one of said jacks forcaus- I ing the flow of signaling current into the section of the lineassociated with the other one of the other ofiices, and means actuatedby the response of the operator at an intermediate oflice to indicate tothe operator at the other terminal ol'lice that the portion of the lineextending between said one terminal otlice and the said intermediateoilice is busy.

7. In combination, a. telephone line comprising a short otlicc sectionat an intermediate station, normally closed contacts at the ends of saidshort section, signaling means bridged across the section with anormally open switch in the bridge and means for opening the contacts oneither side and simultaneously closing said switch.

8. In combination, a telephone line comprising a short intermediateofiice section, normally closed contacts at the ends of this section,signaling means, an operators cord circuit and means for opening thecontacts on one side and connecting said cord circuit to the line onthat side and simultaneously connecting the signaling means across thesand short section.

9. In combination, a telephone line, a

sourceot' tone current at an intermediate point thereof, an" operatorscord circuit, and means for interrupting the line and connecting thecord circuit toone side and simultaneously associating said source withthe other side. i

10. In combination, .a telephone line, means for interruptingit andestablishing a talkinp connection either Way from the point 01'interruption and 7 simultaneously applying signaling current the other'way.

11.. In a signaling system a telephone line, an intermeoiate ofiicethereoman' operators cord circuit set atisaid intermediate office, twojacks at'said office, and meansoperated by the connection of the cordcircuit with October, 1919. I

JOHN F. TOOMEY.

